1. Field of the Invention
The present invention relates to a cell assembly in which a plurality of single cells packaged by laminate films are connected in series and/or in parallel.
2. Description of the Related Art
In recent years, electric vehicles which use electricity as the power source and hybrid cars which run by the combination of an engine and a motor have attracted attention under the environment where the air pollution due to exhaust gas from automobiles has been a global problem. In this connection, development of high-power batteries to be mounted on these types of vehicles, which achieve high energy/power densities, has occupied an important position in the industry.
For this type of high-power battery, for example, there is a lithium-ion battery. As the lithium-ion battery, a stacked cell has been known. In the stacked cell, a power generation element includes planar positive and negative electrode plates, which are stacked with one another by interposing separators therebetween. Both surfaces of the power generation element are sandwiched between a pair of laminate films, and peripheral portions of the laminate films are joined to each other by thermowelding, thus sealing an electrolyte together with the power generation element.
With regard to the single cell packaged by the foregoing laminate films, the one in which a cell assembly having the plurality of single cells arranged in parallel is fixed on a metal plate to configure a battery pack is disclosed in, for example, Japanese Patent Laid-Open Publication 2002-100337.